The present invention concerns light bulbs particularly of the incandescent type having a single filament or multiple filaments adapted to be variably connected to a power source.
In U.S. Pat. No. 4,121,134 there is described an incandescent light bulb having multiple filaments and using a socket adapter threaded into a standard socket. The adapter has a spring contact connected to the voltage connection which is successively engagable with each of a series of side contacts on the bulb base. Each side contact is electrically connected with a respective filament so that each filament is successively energized as the bulb base is rotated in the adapter. This allows the bulb to be kept in service by merely rotating the bulb to a new position as each filament burns out.
However, the spring contacts are bulky and prone to failure.
Also, it would be desirable if other functional combinations of the power connections to a single or multiple filament bulb were possible, which are not enabled by the above-described arrangement.
Such other functional combinations include connecting more than one filament in a multiple filament bulb to create varying wattage or applying different voltages to a single filament bulb.
Accordingly, it is an object of the present invention to provide a compact and simple arrangement for providing varying electrical connections to a light bulb.
It is a further object to provide such an arrangement which enables functional combinations of the power connections to a single light bulb filament or to multiple light bulb filaments.